Process for the sulfonation of peroxidized, deperoxidized unsaturated fatty acid esters and product



United States Patent 10 Claims. (31. 260-400) This invention relates to sulfonated oil products and to the method for producing such products. It more particularly relates to sulfonated oils which are useful in the finishing treatment of leathers.

Sul-fation products of animal and vegetable oils, which are commonly used for leather fatting, produce leather of satisfactory softness and adequate fullness when used alone or in combination with natural fats of animal, vegetable or mineral origin, but the leather is not always satisfactory with respect to its strength and smoothness of the grain. An improvement of the grain can be achieved by using true sulfonation products of animal or vegetable oils in place of the sulfation products for leather fatting. However, this has been found to have the disadvantage that leathers with less fullness and less softness are obtained. These detrimental effects can be overcome within certain limitations by compounding the oil sulfonates with neutral oils and synthetic emulsifiers, but this requires a cumbersome trial and error testing procedure from one case to another.

It is therefore an object of this invention to provide a method for producing sulfonated oils from unsaturated fatty acid esters.

Another object is to produce a fat liquoring agent for leather which has good oiling effects for leather to give adequate softness and fullness while, at the same time, giving adequate strength and smoothness of grain.

These and other objects of our invention will become apparent as the description thereof proceeds.

It has now been found that very good fatting effects with simultaneous excellent fullness and firmness of the grain in the leather can be achieved by using for the fatting treatment sulfonation products of unsaturated fatty acid esters which are obtained by treatment of certain animal, vegetable or synthetic unsaturated oils or fats with a mixture of sulfur trioxide and air or sulfur trioxide and an inert gas. The oils and fats are peroxidized prior to this treatment by intensive aeration and are subsequently deperoxidized.

For this purpose the unsaturated fatty acid esters are subjected to an intensive aeration or to a treatment with other oxygen-containing gas mixtures at a temperature of 6S-100 C. with or without the addition of an oxidation catalyst, such as cobalt oleate, manganese oleate, or lead oleate, until a peroxide number of 200-700 is reached. Particularly favorable results with respect to the end products are furnished by the oxidative aeration without the addition of a catalyst at a reaction temperature of 80100 C. This is followed by a thermal treatment at 110-160 0., preferably 150 C, whereby the peroxidized oil is again deperoxidized until the peroxide number has dropped to 0.

Only subsequent to this treatment the sulfonation with 15%, preferably sulfur trioxide in the form of a sulfur trioxide-air or sulfur-trioxide-ine-rt gas mixture with a sulfur trioxide content of 2-10%, preferably 37%, is carried out at a temperature of 0-20 C. in discontinuous or continuous fashion.

If the sulfur trioxide sulfonation is performed prior to ice the deperoxidation, that is, on the peroxide-containing material, very dark products are obtained and the reaction proceeds with a very pure sulfur trioxide absorption. Subsequent to the sulfonation, the acid reaction product is bleached with hydrogen peroxide, advantageously at a temperature of 5070 C., and after careful neutralization and removal of the water by distillation, yields stable, blank, slightly reddish oils which produce an excellent softening effect upon the leather.

Preferred starting materials for the sulfonation products according to the present invention are weakly unsaturated fatty acid esters of natural or synthetic origin which do not contain hydroxyl groups. Examples of natural unsaturated oils are sperm oil, olive oil, neatsfoot oil, corn oil, mustard oil, rice oil, cottonseed oil and teaseed oil, but no limitation to these oils is intended. Examples of synthetic unsaturated Oils are triolein (technical grade oleic acid glycerin ester) and oleic acid oleyl ester. The sulfonation products may be employed by themselves, in combination with natural oils (fatty oils, mineral oil), and for variation of the fatty effects also in combination with other known emulsifiers of anionic or nonionic type and natural oils.

The sulfonation step may also be performed by means of other methods, such as are known for the sulfur trioxide sulfonation, that is, by sulfonation with sulfur trioxide in solvents or in sulfur dioxide, for example.

The following specific examples are presented to illustrate the invention and to enable persons skilled in the art to better understand and practice the invention and are not intended to be limitative.

Example I A vigorous stream of air was passed through 400 gm. of sperm oil at a temperature of C. for 6-7 hours while stirring, whereby a peroxidized product with a peroxide number of 700 was formed. Thereupon, the stream of air was shut off and the reaction product was heated for a half hour at C. accompanied by stirring, whereby the peroxide number dropped back to 0.40 gm. of sulfur trioxide in the form of a 5% sulfur trioxide-air mixture were passed through this deperoxidized sperm oil at a temperature of l0-l2 C. accompanied by cooling and thorough agitation. After addition of 40 gm. of water and 20 gm. of 40% hydrogen peroxide at 60 C. accompanied by stirring, the sulfonation product obtained thereby was bleached for two hours. Subsequently, while thoroughly cooling, during which time the temperature must not rise, above 20 C., the sulfonation product was neutralized with sodium hydroxide and was then dehydrated in vacuo. A clear, slightly colored oil was obtained which remained uniform even after prolonged storage and exhibited no deposits or other changes.

Chrome tanned uppers were fat-liquored in a vat at 60 C. for a period of 45 minutes by means of 250% solution containing 5-6% of the above described fat-liquoring substance. Smooth, firm grained uppers with a full smooth feel, excellent softness, light coloration and a very good light fastness were obtained.

Example II A sperm oil sulfonation product was produced analogous to Example I, except that under otherwise completely identical conditions the amount of sulfur trioxide introduced into the sperm oil was increased to 60 gm.

Chrome tanned uppers were fat-liquored in a vat at 60 C. for 45 minutes by means of 250% solution containing 5-6% of the above fat-liquoring substance. After drying, smooth, firm grained upper leather with good feel, excellent softness, light coloration and good light fastness was obtained. A similar result was obtained when a mixture of 70% of the above-mentioned sperm 3 oil sulfonation product and 30% sperm oil filtrate having a solidification point of 8 C. was used as the fat-liquoring substance.

Example III 300 gm. of triolein were subjected to at treatment with air analogous to Example I at a temperature of 90 C. for ten hours, whereby a reaction product with a peroxide number of 280 was obtained. This product was deperoxidized by heating to 150 C. for a half hour until it had a peroxide number of 0, and subsequently thereto the deperoxidized product was reacted with 30 gm. of sulfur trioxide in the form of a 5% sulfur trioxide-nitrogen mixture at a temperature of 8l5 C. After bleaching with 15 gm. of a 40% hydrogen peroxide solution, neutralization and dehydration a clear, slightly reddish product was obtained which did not undergo any change Whatsoever upon prolonged storage.

Pastel colored glove leather made of lamb skins were fat-liquored in a vat at 60 C. over a period of 45 minutes by means of 250% solution containing 5-6% of the above mentioned sulfonation product as the fat-liquoring substance (based on the leather), and the leather was dried and finished. Full, soft and supple glove leather Was obtained which was light fast and had a firm grain.

Example IV 400 gm. of teaseed oil were treated with air analogous to Example I at 90 C. over a period of 8 hours until a peroxide number of 350 was reached. The reaction product was deperoxidized to a peroxide number of by heating to 150 C. over a period of a half hour, and subsequent thereto the deperoxidized product was reacted with 40 gm. of sulfur trioxide with a sulfur trioxideair mixture. After bleaching with 20 gm. of 40% hydrogen peroxide, neutralization and dehydration analogous to Example I, a clear, slightly reddish oil was obtained which was completely stable even upon prolonged storage.

When chrome tanned uppers were fat liquored with 5-6% of the above sulfonation product analogous to the method described in Examples I and II, satisfactorily lightfast, light-colored, soft uppers having a full feel and firm grain were obtained.

When glove leather made of lamb skins was fat liquored in a vat at 60 C. over a period of 45 minutes with 250% solution containing 46% of a mixture of 70% of the above sulfonation product 10% teaseed oil mineral oil of 3.44 E/ C., and

5% of an addition product of 510 mols of ethylene oxide to 1 mol of a fatty alcohol C C as the fat liquoring substance (based on'the leather), dried and finished in the usual manner, full soft and supple glove leather with good light-fasteness was obtained.

While certain specific examples and preferred modes of practice of the invention have been set forth it will be understood that this is solely for the purpose of illustration and that various changes and modifications may be made without departing from the spirit of the disclosure and the scope of the appended claims.

We claim:

1. A process for the production of sulfonated fatting agents from unsaturated hydroxyl group free fatty materials selected from the group consisting of natural and synthetic fats and oils, which comprises the steps,

(a) peroxidizing said fatty materials by treatment with 4 oxygen containing gases at temperatures of from to C.,

(b) deperoxidizing by heat treatment at temperatures of to 160 C.,

(c) and thereafter sulfonating by reaction with 5 to 15% of sulfur trioxide at temperatures from 0 to 20 C.,

(d) bleaching said sulfonated products with hydrogen peroxide,

(e) and neutralizing said bleached products.

2. A sulfonated oil product as produced by the process of claim 1.

3. Process according to claim 1, wherein the oxidative treatment with air of the unsaturated fatty acid ester is carried out without the addition of a catalyst at a temperature of from about 80100 C.

4. Process according to claim 1, wherein the deperoxidation is performed at a temperature of 110160 C.

5. Process according to claim 1, wherein the deperoxidation is performed at a temperature of about C.

6. Process according to claim 1, wherein the sulfonation is accomplished with a 2-10% mixture of sulfur trioxide and a gas selected from the group consisting of air and an inert gas, at a reaction temperature of 0 to 20 C., from about 5-15% of sulfur trioxide being used, based on the amount of deperoxidized oil.

7. Process according to claim 1, wherein the sulfonation is accomplished with a mixture of about 37% sulfur trioxide and a gas selected from the group consisting of air and an inert gas, at a reaction temperature of 0 to 20 C., from about 5l5% of sulfur trioxide being used, based on the amount of deperoxidized oil.

8. Process according to claim 1, wherein the sulfonation is accomplished with a mixture of about 37% sulfur trioxide and a gas selected from the group consisting of air and an inert gas, at a reaction temperature of about 020 C. 10% of sulfur trioxide being used, based on the amount of deperoxidized oil.

9. Process according to claim 1, wherein weakly unsaturated natural and synthetic fatty acid esters are used as starting materials.

10. A process for the production of sulfonated fatting agents from unsaturated hydroxyl group free natural fats and oils, which comprises the steps,

(a) peroxidizing said natural fats and oils by treatment with oxygen containing gases at temperatures of from 65 to 100 C.,

(b) deperoxidizing by heat treatment at temperatures of 110 to C.,

(c) and thereafter sulfonating by reaction with 5 to 15% of sulfur trioxide at temperatures from 0 to 20 C.,

(d) bleaching said sulfonated products with hydrogen peroxide at temperatures of 50 to 70 C.,

(e) and neutralizing said sulfonated products.

References Cited by the Examiner UNITED STATES PATENTS 1,926,442 9/1933 Gunther et al 260400 FOREIGN PATENTS 296,935 9/ 1928 Great Britain. 330,904 6/ 1930 Great Britain. 362,971 10/1931 Great Britain.

CHARLES B. PARKER, Primary Examiner.

ANTON H, SUTTO, Assistant Examiner. 

1. A PROCESS FOR THE PRODUCTION OF SULFONATED FATTING AGENTS FROM UNSATURATED HYDROXYL GROUP FREE FATTY MATERIALS SELECTED FROM THE GROUP CONSISTING OF NATURAL AND SYNTHETIC FATS AND OILS, WHICH COMPRISES THE STEPS, (A) PEROXIDIZING SAID FATTY MATERIALS BY TREATMENT WITH OXYGEN CONTAINING GASES AT TEMPERATURES OF FROM 65 TO 100*C., (B) DEPEROXIDIZING BY HEAT TREATMENT AT TEMPERATURES OF 110 TO 160*C., (C) AND THEREAFTER SULFONATING BY REACTION WITH 5 TO 15% OF SULFUR TRIOXIDE AT TEMPERATURES FROM 0 TO 20*C., (D) BLEACHING SAID SULFONATED PRODUCTS WTH HYDROGEN PEROXIDE, (E) AND NEUTRALIZING SAID BLEACHED PRODUCTS. 